The present invention relates to a method of textile printing by microorganism and a microorganism for decolorization of azo system dye. More specifically, the present invention relates to a textile printing method using a specific bacterium, comprising treating a base material colored with an azo-system dye or with an azo-system dye together with a non azo-system dye or a base material with a pattern printed thereon by means of a paste solution containing at least the specific bacterium (and another azo-system dye. Additionally, the present invention also relates to a microorganism for decoloring azo system dyes. The microorganism being capable of metalizing the azo system dyes.
The term "textile printing" includes direct textile printing (printing a pattern on a white base material or a ground dyed base material), discharge printing printing a patter on a ground dyed base material (including white discharge printing, colored discharge printing and semi-discharge printing)! and reserve printing (comprising dyeing after drawing a pattern with a substance inhibiting the dyeing).
For the "discharge printing", there is carried out 1. "white discharge printing" comprising depositing a paste solution containing a reducing agent or an alkali on primarily solid dyed cloth following a desired pattern for thermal processing, to facilitate decolorization via the reduction or the saponification of the carboxylate of a dispersion dye, thereby producing the pattern in white; 2. so-called "colored discharge printing" comprising effecting bleaching along with dyeing with another color; and 3. "semi-discharge printing" comprising terminating the white discharge printing during its intermediate stage, thereby leaving a pattern in slightly paler color than the base color. Furthermore, the "direct textile printing" comprises coating (printing, etc.) a given pattern on a base material using a predetermined color paste, subsequently drying the material, and steaming and washing the material for final finishing.
According to the aforementioned textile printing methods (the color discharge printing in particular), a reducing agent or an alkali is used for bleaching, so that it is required that the dye for preliminary solid dyeing (so-called dye for ground dyeing) should be a dye which can be decolored readily. Furthermore, the textile printing is limited in that the printing dye (dye of effect color for printing) should be a dye resistant to reduction and a alkalis during decolorization. The textile printing is disadvantageous in that cloth may be damaged with reducing agents and that halation (blurring in the border of colors) may occur readily.